When the aircraft climbed through about FL120 at 275 KIAS the crew noticed a hot air balloon dragging a plastic banner which contacted the aircraft. Immediately afterwards all airspeed indications disagreed and autopilot and autothrust disconnected, messages "MAINTENANCE STATUS F/CTL", "NAV ADR DISAGREE", "F/CTL ALTN LAW", "AUTO FLT AP OFF", "AUTO FLT A/THR OFF" and "NAV ALTI DISCREPANCY" were shown on ECAM. The captain instructed the first officer to disregard the "NAV ADR DISAGREE" message and did not inform Air Traffic Control. The crew attempted to reconnect the flight directors and autopilot however without success. The crew partially executed the unreliable speed checklists - while the first officer read the checklist the commander switched the ADR data sources and identified ADR3 as not working, the crew however did not rearrange the systems to use ADR1 and ADR2 instead. Subsequently the crew referred to the pitch/power tables using an aircraft weight of 66 tons although the actual aircraft weight was 54 tons and the table for 56 and less tons should have been used. Although the aircraft was no longer compliant with requirements for RVSM airspace, the crew did not notify ATC and continued the climb manually into RVSM airspace levelling off at FL310. Throughout the flight a multitude of alerts regarding deviations from altitude and heading occurred. During the descent air traffic control complained the aircraft was 1nm off track and queried whether they would be able to conduct an ILS approach to Belo Horizonte. The crew configured the aircraft for flaps on the ILS approach to Belo Horizonte's runway 13, the captain identified the speed indications of left and right PFD disagreed by more than 10 knots with the first officer's instrument showing the higher value, the captain decided to use the first officer's indications without checking whether his or the first officer's indications were more reliable.
Originally posted by CENIPA
Comment